The Problem with Current Noise Suppression Schemes for Mobile Phones

Many electronic devices employ voice-related features that involve recording and/or transmitting a user's voice. Voice note recording features, for example, may record voice notes spoken by the user. Similarly, a telephone feature of an electronic device may transmit the user's voice to another electronic device. When an electronic device obtains a user's voice, however, ambient sounds or background noise may be obtained at the same time. These ambient sounds may obscure the user's voice and, in some cases, may impede the proper functioning of a voice-related feature of the electronic device.

To reduce the effect of ambient sounds when a voice-related feature is in use, electronic devices may apply a variety of noise suppression schemes. Device manufactures may program such noise suppression schemes to operate according to certain predetermined generic parameters calculated to be well-received by most users. However, certain voices may be less well suited for these generic noise suppression parameters. Additionally, some users may prefer stronger or weaker noise suppression.

Apple's Solution

Apple's invention relates to systems, methods, and devices for user-specific noise suppression while substantially preserving the user voice via user-specific noise suppression parameters. These user-specific noise suppression parameters may be based at least in part on a user noise suppression preference or a user voice profile, or a combination thereof.

Apple's patent FIG. 3 illustrates many such contexts in which the iPhone may obtain a user voice audio signal (58) and ambient sounds (60) while performing a voice-related feature.

Apple's patent FIG. 5 illustrates a block diagram representing user-specific noise suppression parameters.

Voice Training

Voice training, as noted as patent point 104 on patent FIG. 5 above, may allow the iPhone to determine the user-specific noise suppression parameters (102) by way of testing a variety of noise suppression parameters combined with various distractors or simulated background noise. New noise suppression features will be made available under the iPhone's "Settings" covering a noise suppression strength selector (e.g., low/medium/high) and/or a real-time user feedback selector to provide user feedback regarding the user's real-time voice quality.

Apple's patent FIGS.10 and 11 shown below are schematic diagrams for a manner of obtaining a user voice sample for voice training; patent FIG. 12 is a schematic diagram illustrating a manner of obtaining a noise suppression user preference during a voice training sequence.

While a user may be able to further tweak the future iPhone's noise suppression levels for varying situations over time, Apple appears to have set up a unique noise suppression system using a dual-device recording system as noted in patent FIG. 10 as an initial set-up system. During the operation of the system (180), the MacBook or other Mac may prompt the user to say a word or phrase while one or more of a variety of distractors play in the background (182). Such distractors may include sounds of crumpled paper babbling people, white noise, rock music, and/or road noise. The user will then set up the noise suppression levels of their choosing.

Apple's patent FIG. 17 noted below is a factor diagram describing characteristics of a user voice sample that may be considered; patent FIG. 18 is the new iPhone setting screenshots for accessing noise suppression setting; and patent FIGS. 27-29 are plots depicting a manner of performing noise suppression of an audio signal based on a user voice profile.

Apple's patent application was originally filed in Q2 2010 by inventors Aram Lindahl and Baptiste Pierre Paquier.

Other Noteworthy Patent Applications Published Today

There were two additional patents published today relating to noise suppression and sound quality on future iPhones. Apple's second patent deals specifically with active noise cancellation (ANC) circuitry that is coupled to the input of an earpiece speaker of an iPhone to control the ambient acoustic noise outside of the device and that may be heard by a user of the device. A microphone is to pickup sound emitted from the earpiece speaker, as well as the ambient acoustic noise. Control circuitry deactivates the ANC in response to determining that an estimate of how much sound emitted from the earpiece speaker has been corrupted by noise indicates insufficient corruption by noise.

Apple's patent FIG. 1 depicts a mobile communications device in use by a user in a hostile acoustic environment; FIG. 4 is a plot of intelligibility versus SNR for sentences and single-syllable words; FIG. 5 is a block diagram of feed forward ANC and ANC decision control based on signal and noise estimates.

Apple's third patent on this subject matter covers their invention that generally relates to methods and systems for removing time division multiple access (TDMA) noise from an audio signal.

Speakerphone Mode coming to iPad

The last patent covers Apple's invention relating to echo cancellation techniques within a communications device such as a smart phone and a cellular phone, for reducing the presence of an undesired reverberated audio signal in an uplink signal path of the device.

But there's a surprise to this patent: In patent FIG. 1we clearly see two users, one with an iPhone and the other with an iPad. What's new here is that Apple states that "a far-end user (depicted in this case as using a tablet-like computer is also in speakerphone mode)." Yes, a speakerphone on the iPad.

Apple credits Stephen Schell for this invention which was originally filed in Q2 2010.

On another front today, Apple has filed a divisional application relating to their original 3D UI patent that we covered in our September report titled "Whoa - Apple Wins a 3D Display & Imaging System Patent Stunner." While I couldn't find anything new in the patent that stood out, it's still nice to know that it's a current project. The filing date on this version of the filing is noted as being August 2011 or four months ago. Is someone sending us a message here? In time, we'll know. But for now, it sure sounds good to me!

Oh, by the way, I see that my competition is making it out to be an all new patent. Ha! I guess that they didn't get the memo. 

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